1. Field of the Invention
This invention generally relates to data transfer rates, and particularly to an apparatus and method for testing a data transfer rate.
2. Description of Related Art
Nowadays, electronic devices, such as personal computers, digital cameras, and portable audio/video players, are widely used for a variety of applications. An electronic device usually includes a data transfer interface for transmitting data, such as a Universal Serial Bus (USB) interface or an IEEE 1394 interface etc. For example, an MP3 player downloads songs from a personal computer via the USB interface.
Most people are concerned about data transfer rates between the electronic devices. For example, when someone is going to download a plurality of MP3 files to the MP3 player, a shortest time for downloading the MP3 files is desired. Although a maximum data transfer rate of one specific interface is a constant value, for example, the maximum data transfer rate of USB 2.0 is 480 Mbps. An actual data transfer rate of the specific interface is variable according to different application environments. The actual data transfer rate is affected by many factors, such as an interface controller, data transfer circuit layout, and electromagnetic environment. That is, the actual data transfer rates of different electronic devices are different even when using the same interface standard. Some electronic devices are screened out during data transfer rates testing. If the data transfer rates of the electronic devices are too low, the devices are ineligible to be labeled with the particular data transfer rates rating.
In order to screen out ineligible electronic devices, standardized tests are performed. Traditionally, a storage device is employed in the tests. The storage device is connected to the electronic device for receiving a predetermined file transmitted from the electronic device. If a transmission time of the predetermined file is no more than a predetermined time, the electronic device is eligible. However, if a transmission time of the predetermined file is more than the predetermined time, the electronic device is ineligible.
Reliability is also a factor in the testing of data transfer rates. If the data transfer rate of the electronic device is not reliable, while the predetermined file in the electronic device is copied to the storage device in the predetermined time. The electronic device will be recognized as an eligible electronic device according to the traditional testing method. That is, the traditional testing method is not able to test a stability of the data transfer rate. The electronic device is considered to be eligible even if the data transfer rate of the electronic device is not reliable.
Therefore, an improved method and apparatus for testing the data transfer rate are desired.